WASHINGTON - Making his case for war with Iraq, President Bush in his State of the Union address this year accused Saddam Hussein of trying to buy uranium from Africa, even though the CIA had warned White House and other officials that the story did not check out.

A senior CIA official, who spoke on the condition of anonymity, said the intelligence agency informed the White House on March 9, 2002 -- 10 months before Bush's nationally televised speech -- that an agency source who had traveled to Niger could not confirm European intelligence reports that Iraq was attempting to buy uranium from the West African country.

Despite the CIA's misgivings, Bush said in his State of the Union address: "The British government has learned that Saddam Hussein recently sought significant quantities of uranium in Africa."

Three senior administration officials said Vice President Dick Cheney and some officials on the National Security Council staff and at the Pentagon ignored the CIA's reservations and argued that the president and others should include the allegation in their case against Saddam.

Forgeries involved

The claim later turned out to be based on crude forgeries that an African diplomat had sold to Italian intelligence officials.

The revelation of the CIA warning is the strongest evidence to date that pro-war administration officials manipulated, exaggerated or ignored intelligence information in their eagerness to make the case for invading Iraq.

"We've acknowledged that some documents were forged, and we know now it was a mistake to give them credence," said a fourth senior administration official who defended the White House's handling of the matter.

"But they were only one piece of evidence in a larger body of evidence suggesting that Iraq attempted to purchase uranium from Africa."

Noting that Iraq had obtained uranium from Africa in the 1980s, he said the most recent allegations "were not central pieces of the case illustrating Iraq's possession of weapons of mass destruction and their WMD programs."

The CIA's March 2002 warning about Iraq's alleged uranium-shopping expedition in Niger was sent to the Defense Intelligence Agency, the Joint Chiefs of Staff, the Justice Department and the FBI the same day it went to the White House, the CIA official said.

In the months before the State of the Union speech, the CIA official said, agency personnel told the State Department, National Security Council staffers and members of Congress that they doubted Iraq had been trying to buy uranium from Niger.

One senior administration official, also speaking on the condition of anonymity because the intelligence reports remain classified, said the CIA's doubts were well-known and widely shared throughout the government before Bush's speech.

Secretary of State Colin Powell didn't include the uranium story in his Feb. 5 presentation on Iraq to the United Nations Security Council, and senior CIA officials excluded it from their assessments of Iraq's illicit weapons programs and from their congressional testimony.

Among the most vocal proponents of publicizing the alleged Niger connection, two senior officials said, were Cheney and officials in the office of Defense Secretary Donald Rumsfeld.

The effort was led by Robert G. Joseph, the top National Security Council staff official on nuclear proliferation, the officials said.

Cheney alleged in an Aug. 26, 2002, speech that Saddam "has resumed his efforts to acquire nuclear weapons," and this March 16 he went much further, saying: "We believe he has, in fact, reconstituted nuclear weapons."

Unaware of CIA doubts

On last Sunday's television talk shows, national security adviser Condoleezza Rice said the White House was unaware of the CIA's doubts.

"Maybe someone knew in the bowels of the agency, but no one in our circles knew that there were doubts and suspicions that this might be a forgery," she said on NBC.

The CIA's March 2002 warning about the Niger connection was just one in a daily flood of diplomatic and intelligence reports on Iraq, and it's possible that Rice never saw it.

However, the inclusion of the uranium story in Bush's speech appears to support charges that some pro-invasion officials ignored intelligence that could hurt the administration's case that Saddam was pursuing nuclear, chemical and biological weapons programs.

Rep. Henry Waxman of Los Angeles, the senior Democrat on the House Intelligence Committee, has demanded that the White House explain why the Niger uranium story was in the president's State of the Union address.

The report of an Iraq-Niger deal was exposed as a fraud when U.N. nuclear officials determined that the documents on which the allegations were based -- reportedly letters between Iraqi and Niger officials -- were forgeries.

The signature on a letter purportedly from Niger's President Tandja Mamadou was an obvious forgery; another letter was on the wrong letterhead and signed by an official who had left the post a decade earlier.

The use of the false evidence despite the CIA warning raises questions about why some officials chose to believe the story despite the widespread skepticism in the intelligence community.

Different intelligence

One possibility, one senior official suggested Thursday, is that some officials at the Pentagon and in the vice president's office were getting their own intelligence from Iraqi exiles who the CIA and the Defense Intelligence Agency warned could not be trusted.

Exile leader Ahmad Chalabi of the Iraqi National Congress told lawmakers Thursday that his group had turned three Iraqi defectors over to U.S. officials.

One of the three, Chalabi said, was an Iraqi scientist who was involved in separating isotopes for Iraq's nuclear weapons program.

Bush cited allegations that Saddam was hiding chemical, biological and nuclear warfare efforts from U.N. inspectors as a main justification for the U.S.-led war.

After more than two months of searching, U.S. troops have not discovered any illicit weapons stockpiles or any evidence that Saddam had reconstituted his nuclear weapons program.

Majority Republican lawmakers so far have spurned a public investigation, but the Senate Intelligence Committee has begun reviewing intelligence assessments of Iraq's illicit weapons programs and will start closed-door hearings next week.